A dark surgeonfish that grazes fine growth off rock, taking small bites in a continuous line.
To about 27 or 30 cm. Dark grey-brown, covered in numerous small brilliant blue spots over the head, body and pectoral fins, with blue pinstripes along the dorsal, anal and tail fins. The body is elongate-oval and strongly compressed. The mouth is small and set low on the head, with flexible curved comb-like teeth — about forty-four in the upper jaw and sixty in the lower.
Those teeth are the identification and the behaviour that goes with them. It brushes detritus and diatoms off surfaces rather than scraping rock, which is what separates it from the true surgeonfish that share its reefs.
It lives on shallow wave-washed rock and coral, roughly between the surface and 40 m and typically around 10 m. It is the only fish of its genus recorded anywhere in the eastern Pacific, and it is sparse there: the Revillagigedo record is real and comes from the Smithsonian’s own checklist for the archipelago, but neither of the main reference works mentions Revillagigedo in its range statement, and the species is explicitly absent from the Galapagos. Do not expect to see it.
FishBase now calls it the bluespotted surgeonfish, and this site follows that, with the older name kept here so a reader cross-checking a database finds the same fish.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.